Several industries have utilized linear actuators to control the movements of automated fixtures. This requires controlled linear movement of the type that is produced by linear actuators, which can be driven by various mechanisms, including electric, pneumatic or hydraulic actuators. Linear actuators work by extending and retracting a thrust member, usually with a work piece affixed to its end to perform certain tasks. Particularly, electric actuators typically include a thrust tube assembly, a screw shaft, a bearing journal assembly, and a work piece connection end. A motor shaft can be coupled to the bearing journal assembly to rotate the journal assembly, and thereby the screw shaft. The screw shaft engages a nut coupled with the thrust tube assembly, which transfers rotary motion of the screw shaft into linear motion of the thrust tube assembly. The work piece connection end can support a variety of tools depending on the use of the particular actuator.
However, the manufacture of these devices can often be complicated and not always cost-effective. This can be especially true with regard to the assembly of the thrust tube and bearing journal assemblies. Often, the nut needs to be mechanically coupled with a thrust tube to form the complete thrust tube assembly. The process requires a significant amount of time and exactness to form a well-working actuator. The difficulty of the process is further intensified when the parts being worked on, such as the nut, are relatively small.
Thus, there exists a need in the art for an improved method of manufacturing a screw-driven linear actuator. This includes a need for a simpler method of manufacturing, using less connective parts and a less intensive process. There is also a need in the art for a more cost effective technique for assembling an actuator.